Home Forums PID Control / Tuning Setpoint crossing keeps waiting

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  • Deusjevoo
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    Post count: 3

    While testing, below profile (not a real profile, just some values to test, noticed something.
    The red line is the controler TC.

    If you cross a setpoint faster then the giving time, it keeps waiting for crossing it.
    LIke here, in the “1, 100, 60 //ramp setpoint to 100 over the course of 60 seconds” step.
    Powerfull heaters, it crossed the 100c befor the 60 sec.
    Got overshoot, it kept waiting around 120c as it was allready above setpoint of 100c.
    At +/- 3:40 switched on a fan, temp droppod belowe 100c.
    As soon as it was below 100c again osPID went to next step.
    On the next step however, it just kept on going.
    Don’t think it would’ve stopped, switched it off myself.

    Dangerous !!!

    Leaded //first row is Profile Name
    3, 30, 0 //Step Setpoint to 30, wait 0 seconds
    2, 0, 0 //Wait for PID Input to cross setpoint
    1, 100, 60 //ramp setpoint to 100 over the course of 60 seconds
    2, 0, 0 //Wait for PID Input to cross setpoint
    1, 120, 30 //ramp setpoint to 180 over the course of 90 seconds
    2, 0, 0 //Wait for PID Input to cross setpoint
    1, 150, 45 //ramp setpoint to 220 over the course of 90 seconds
    2, 0, 0 //Wait for PID Input to cross setpoint
    1, 180, 45 //ramp setpoint to 180 over the course of 30 seconds
    2, 0, 0 //Wait for PID Input to cross setpoint
    1, 50, 150 //ramp setpoint to 50 over the course of 150 seconds
    2, 0, 0 //Wait for PID Input to cross setpoint
    127, 0, 5 //buzz for 5 seconds

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